Questions & Answers about Hleðslutækið er í bílnum og rafhlaðan er tóm líka.
Yes. Icelandic adds the definite article as an ending:
The preposition í (“in/into”) governs:
- Dative for location (being somewhere): í bílnum = in the car.
- Accusative for motion/direction (into): í bílinn = into the car. Your sentence is about location, so dative (bílnum) is correct.
Because it’s a predicative adjective (after “is”), and predicative adjectives normally take the strong endings. For “empty”: